GMC W7500 Forward Headlight Bulb Size

Additional Notes

• The GMC W7500 Forward uses sealed beam headlight units across all listed model years from 1984-1996. Sealed beam units integrate the filament, reflector, and lens into a single assembly, meaning the entire unit requires replacement rather than an individual bulb.
• All six bulb types specified for this vehicle, H5001, H6054, H6024, H4651, H5006, and H4656, conform to ANSI standards recognized in both the United States and Canada, and all operate at 12 volts.
• The W7500 Forward Tiltmaster variant uses a distinct set of sealed beam units from the rest of the lineup. The Tiltmaster takes the H5001 (4-inch square) for high beam and the H5006 (5.75-inch round) for low beam, neither of which is shared with the 2-rectangular or 4-rectangular headlamp configurations.
• Configurations equipped with 2 rectangular headlamps use the H6054, a 5x7-inch rectangular sealed beam unit, for both high and low beam functions. This dual-purpose application across both beam types is a notable fitment characteristic of that specific configuration.
• The H4651 and H4656 are both 4x6-inch rectangular sealed beam units serving 4-rectangular headlamp configurations, with H4651 designated for high beam and H4656 for low beam. Despite sharing the same physical format, these two units are not interchangeable due to their differing beam functions.
• Configurations with 2 round headlamps use the H6024, a 7-inch round sealed beam unit, for both high and low beam. This configuration does not appear in the 1989-1991 model years within the specifications, though it is present in 1984-1988 and 1992-1995.
• The H5001 and H5006 share the same application notes for 1985-1987, where both are listed under "With 4 Round Headlamps or Tiltmaster," indicating those two distinct vehicle configurations used the same sealed beam units during that period.
• The 1996 model year lists only Tiltmaster fitment entries, covering the H5001 for high beam and H5006 for low beam, while all other headlamp configurations present in earlier years are absent from the 1996 data.